6-5/12÷10/9-13/8.

问题描述:

6-

5
12
÷
10
9
-
13
8

6-

5
12
÷
10
9
-
13
8

=6-
3
8
-
13
8

=6-(
3
8
+
13
8
),
=6-2,
=4.